A number of tools are available for the creation of programs having a graphical interface, which facilitate the creation of such programs.
An example is the compiler system ‘Delphi’ of the Inprise company (formerly Borland). In this system, the user places objects of the graphical interface onto a working interface, and assigns properties to them. The classes of these objects are referred to as components in Delphi. The position of the objects is noted by the interface of the compiler system and is filed in resource files. In this way, the objects are predetermined by their position. While it is certainly possible to change the position during the running time, this requires that pixel coordinates be indicated and is therefore complicated.
Such a dynamic adaptation is required, for example, if database inquiries must be represented, the scope of which is only known during the running time after the database query. For this purpose, special components are provided in Delphi, which allow representation of all calculated data in the form of a table, for example. While the properties of the representation can be parameterized, this can only normally be done only within the scope of the planned representation. These planned representations are of a text type and correspond to forms and tabular representations. If another representation is desired, particularly one that visualizes the relationship between the data, either a new specific component has to be created, or the entire graphical configuration must be specially programmed. Either one requires significant, detailed knowledge and is initially unknown to a newcomer to such a system, and is therefore also time-consuming for an expert.
U.S. Pat. No. 5,802,514 presents a system for the representation of database contents that generates a form-oriented representation.
U.S. Pat. No. 6,104,393 shows a system for the integration of procedural and object-oriented user interfaces in which also a representation with forms is selected.
Other tools that were created in the UNIX environment are the programming language JAVA and the Tcl/Tk system. In both, partial systems referred to as ‘layout managers’ are used. In this environment, the displayed graphical objects are also referred to as ‘widgets’ in order to clearly differentiate them from the objects of the programming language. A layout manager arranges objects of the programming language that have been assigned a graphical representation on an interface, if it is displayed or if it has changed in size or in any other way. The graphical objects are made known to the layout manager object, whereby influence can be exerted on their position by way of parameters, without absolute pixel positions being necessary. If the number of objects is predetermined, i.e. if it is fixed during the programming, this procedure works well.
However, if the objects are generated dynamically, and if they are not predetermined, then each case requires a special solution specific to the case.